Liquid crystal display (LCD) has gradually replaced cathode ray tube (CRT) display in recent years due to its characteristics such as smaller size and lighter weight. However, factors affecting the display effect of liquid crystal display, such as grey-scale response speed, are highly related to the surrounding atmospheric environment of the display, such as temperature. To achieve higher quality of display from liquid crystal display, therefore, the user's surrounding environment should be taken into consideration as well. In general, under the identical driving method, the grey-scale response time of a liquid crystal display increases one millisecond when the ambient temperature of the liquid crystal display decreases one degree.
FIG. 1 of the attached drawings is a pictorial representation of the original driving paths. As shown in FIG. 1, the original driving path refers to the driving voltage's variation from its initial driving voltage to the targeted driving voltage under a certain temperature, such as T1 or T2. The original driving path under temperature T1 reaches the targeted driving voltage at a time t1. Since temperature T1 is much higher than T2, the original driving path under temperature T2 reaches the targeted driving voltage at a time t2 that is later than t1. Because of this, the same liquid crystal display could easily be affected by its surrounding atmospheric environment (especially temperature) to have different grey-scale imaging speed and in turn result in significant difference in dynamic image display effect under temperature T1 and T2.
Based on the foregoing description, it should not be difficult to understand that the display effect of a liquid crystal display is closely related to the surrounding atmospheric environment of the liquid crystal display. When driving the liquid crystal of a liquid crystal display, it is therefore required to take into consideration as a factor the surrounding atmospheric environment of the liquid crystal display.
Currently in the industry, LG Philips adopts a technique to take surrounding atmospheric environment factor into consideration as described in Document No. U.S.2003/0107546, titled “Method and Apparatus for Driving Liquid Crystal Display”, published on Jun. 12, 2003. The '546 patent basically utilizes a temperature sensor to detect the ambient temperature of a liquid crystal display, obtaining an appropriate correction from a pre-established Look Up Table (LUT) based on the sensed temperature, and then applying the correction to the output signal of dynamic images.
Samsung adopts another technique to take surrounding atmospheric environment factor into consideration as described in Document No. U.S.2003/0098839, titled “Liquid Crystal Display and a Driving Method Thereof”, published on May 29, 2003. The '839 patent applies correction to the dynamic images' output signal based on correcting parameters derived from temperature, user-determined image quality, and the display related surrounding environment.
The above two industry solutions both require the use of temperature sensors to obtain the ambient temperature of a liquid crystal display before correcting the output of dynamic images. However, both solutions not only require additional cost from the temperature sensors, but also lose flexibility by over-emphasizing the temperature variation. After all, the display effect of a liquid crystal display is not entirely related to temperature variation.